Modern mobile devices provide many functionalities including telephony (e.g., cellular phone, VOIP), PDA (personal digital assistance) (e.g., contact/address list, games, photos), network connectivity (e.g., Internet web browser, email, short message service (SMS), mapping/location services). Generally, the mobile device user explicitly controls which applications/functionalities to use at a given moment. For example, the user might use SMS services (or texting) at any location where there might be network connectivity. Given that the network connectivity has become more prevalent, the mobile device users tend to use the functionality of mobile devices in more places and situations.
An example of these mobile device functionalities is the text messaging (or texting) which is a communication method between mobile devices over cellular networks wherein short written messages are exchanged between mobile telephone devices, using a communication service standard commonly known as SMS. Given the gateways between the IP networks and telephone networks, one or more SMS users may be on one or both types of networks. This messaging service has been extended to Multimedia Messaging Service (MMS) to include multimedia messages, e.g., containing video, still image, and sound.
This method of communication and its underlying technology has grown to such a great level that it has become one of the most widely used form of mobile communication in the world, wherein almost every mobile phone service provider has made it available to its users as part of its service, covering several billions active users, spanning almost every age group.
The typical mobile device (shown schematically in FIG. 6) includes an audio interface (612) block connected to speaker unit (610) and microphone (611) on one side, and digital signal processor (DSP) block (613) on the other side. Audio interface block usually includes a digital-to-analog converter (DAC), being coupled to a speaker, and an analog-to-digital converter (ADC), being coupled to microphone, to digitize the audio voice and to send the digitized voice to DSP for further processing. DSP, which is considered processing heart of the mobile telephone system, communicates with audio interface block and RF interface block (616), and digitally performs such signal processing functions as speech coding/decoding, error detection/correction, channel coding/decoding, signal equalization, and demodulation, as is well-known to those skilled in the art.
Typically, DSP performs under the control of microprocessor/controller (615), and may further be coupled to an application specific integrated circuit (ASIC) block (614), where it can help with the operation of DSP in some application specific functions in the background, as known to those skilled in the art. RF interface block which is coupled to DSP, receives digitally processed base band signal from DSP, and it for example performs quadrature (complex) modulation on the digital base band signal, converts the modulated digital signal to analog form, using digital-to-analog converter, and sends the modulated analog signal to transmitter block (618) for further frequency up conversion to radiofrequency (RF), for wireless transmission through power amplification block (621) and antenna (622).
In the receiving side of mobile telephone system, downlink wireless RF signals are received by the receiver block (619) via the antenna. Receiver block amplifies the received RF signal through an automatic gain control unit, down converts the amplified RF signal to intermediate frequency (IF) by mixing it with a locally generated reference signal (620), and passes the IF signal on to interface block (616) for quadrature (complex) demodulation, with filtering and analog-to-digital conversion as is well-known to those skilled in the art.
Digital signal processor (DSP) block receives the digitized IF signal from the interface block and performs various signal processing techniques such as demodulation, equalization, error detection/correction, and signal detection, and forwards the detected signal (i.e. voice) to audio interface block, to be converted to analog voice, amplitude controlled (i.e. amplified or attenuated) and sent to the speaker block.
As those skilled in the art recognize, most of the above operation is performed under the control of microprocessor/controller block (615). In a typical mobile telephone system, as depicted above, microprocessor/controller block performs such functions as level 2/3 protocol, radio services management, man/machine interface, operating system (OS) software, and short message service (SMS). The operations of both keyboard and display (617) are under the control of the microprocessor/controller. Mobile devices also include local memory/storage (623) used by the processor and/or other components of the system.
As is known to those skilled in the art (and from sources such as printed publications or online technical articles, e.g., WIKIPEDIA®(An Internet community information web site), during the text messaging, microprocessor/controller receives alphanumeric information from the keyboard, uses SMS services software embedded in its memory, converts the alphanumeric information into short message format, and typically sends the generated message to DSP to be processed and sent over the control channel to a short message service center (SMSC), which provides a store-and-forward mechanism to forward the text messages to the intended recipient.
Although this method of communication service has provided unprecedented level of mobile phone subscriber service, it may be desirable to limit/disable the use of some of mobile device features which could cause distraction to the user when the user is engaged in another activity. For example, statistics indicate that the likelihood of being involved in a traffic accident, while driving and using a handheld device, is four times more than any other situations. One the other hand, it may be desirable to enable other mobile device features based on occurrence of events related to the user or environment. For an example, this invention addresses controlling the mobile device features, such as SMS, while the user is in a vehicle.